from test_support import verify,verbose,TestFailed
from string import join
from random import random,randint
# SHIFT should match the value in longintrepr.h for best testing.
SHIFT = 15
BASE = 2 ** SHIFT
MASK = BASE - 1
# Max number of base BASE digits to use in test cases. Doubling
# this will at least quadruple the runtime.
MAXDIGITS = 10
# build some special values
special = map(long, [0, 1, 2, BASE, BASE >> 1])
special.append(0x5555555555555555L)
special.append(0xaaaaaaaaaaaaaaaaL)
# some solid strings of one bits
p2 = 4L # 0 and 1 already added
for i in range(2*SHIFT):
special.append(p2 - 1)
p2 = p2 << 1
del p2
# add complements & negations
special = special + map(lambda x: ~x, special) + \
map(lambda x: -x, special)
# ------------------------------------------------------------ utilities
# Use check instead of assert so the test still does something
# under -O.
def check(ok, *args):
if not ok:
raise TestFailed, join(map(str, args), " ")
# Get quasi-random long consisting of ndigits digits (in base BASE).
# quasi == the most-significant digit will not be 0, and the number
# is constructed to contain long strings of 0 and 1 bits. These are
# more likely than random bits to provoke digit-boundary errors.
# The sign of the number is also random.
def getran(ndigits):
verify(ndigits > 0)
nbits_hi = ndigits * SHIFT
nbits_lo = nbits_hi - SHIFT + 1
answer = 0L
nbits = 0
r = int(random() * (SHIFT * 2)) | 1 # force 1 bits to start
while nbits < nbits_lo:
bits = (r >> 1) + 1
bits = min(bits, nbits_hi - nbits)
verify(1 <= bits <= SHIFT)
nbits = nbits + bits
answer = answer << bits
if r & 1:
answer = answer | ((1 << bits) - 1)
r = int(random() * (SHIFT * 2))
verify(nbits_lo <= nbits <= nbits_hi)
if random() < 0.5:
answer = -answer
return answer
# Get random long consisting of ndigits random digits (relative to base
# BASE). The sign bit is also random.
def getran2(ndigits):
answer = 0L
for i in range(ndigits):
answer = (answer << SHIFT) | randint(0, MASK)
if random() < 0.5:
answer = -answer
return answer
# --------------------------------------------------------------- divmod
def test_division_2(x, y):
q, r = divmod(x, y)
q2, r2 = x/y, x%y
pab, pba = x*y, y*x
check(pab == pba, "multiplication does not commute for", x, y)
check(q == q2, "divmod returns different quotient than / for", x, y)
check(r == r2, "divmod returns different mod than % for", x, y)
check(x == q*y + r, "x != q*y + r after divmod on", x, y)
if y > 0:
check(0 <= r < y, "bad mod from divmod on", x, y)
else:
check(y < r <= 0, "bad mod from divmod on", x, y)
def test_division(maxdigits=MAXDIGITS):
print "long / * % divmod"
digits = range(1, maxdigits+1)
for lenx in digits:
x = getran(lenx)
for leny in digits:
y = getran(leny) or 1L
test_division_2(x, y)
# -------------------------------------------------------------- ~ & | ^
def test_bitop_identities_1(x):
check(x & 0 == 0, "x & 0 != 0 for", x)
check(x | 0 == x, "x | 0 != x for", x)
check(x ^ 0 == x, "x ^ 0 != x for", x)
check(x & -1 == x, "x & -1 != x for", x)
check(x | -1 == -1, "x | -1 != -1 for", x)
check(x ^ -1 == ~x, "x ^ -1 != ~x for", x)
check(x == ~~x, "x != ~~x for", x)
check(x & x == x, "x & x != x for", x)
check(x | x == x, "x | x != x for", x)
check(x ^ x == 0, "x ^ x != 0 for", x)
check(x & ~x == 0, "x & ~x != 0 for", x)
check(x | ~x == -1, "x | ~x != -1 for", x)
check(x ^ ~x == -1, "x ^ ~x != -1 for", x)
check(-x == 1 + ~x == ~(x-1), "not -x == 1 + ~x == ~(x-1) for", x)
for n in range(2*SHIFT):
p2 = 2L ** n
check(x << n >> n == x, "x << n >> n != x for", x, n)
check(x / p2 == x >> n, "x / p2 != x >> n for x n p2", x, n, p2)
check(x * p2 == x << n, "x * p2 != x << n for x n p2", x, n, p2)
check(x & -p2 == x >> n << n == x & ~(p2 - 1),
"not x & -p2 == x >> n << n == x & ~(p2 - 1) for x n p2",
x, n, p2)
def test_bitop_identities_2(x, y):
check(x & y == y & x, "x & y != y & x for", x, y)
check(x | y == y | x, "x | y != y | x for", x, y)
check(x ^ y == y ^ x, "x ^ y != y ^ x for", x, y)
check(x ^ y ^ x == y, "x ^ y ^ x != y for", x, y)
check(x & y == ~(~x | ~y), "x & y != ~(~x | ~y) for", x, y)
check(x | y == ~(~x & ~y), "x | y != ~(~x & ~y) for", x, y)
check(x ^ y == (x | y) & ~(x & y),
"x ^ y != (x | y) & ~(x & y) for", x, y)
check(x ^ y == (x & ~y) | (~x & y),
"x ^ y == (x & ~y) | (~x & y) for", x, y)
check(x ^ y == (x | y) & (~x | ~y),
"x ^ y == (x | y) & (~x | ~y) for", x, y)
def test_bitop_identities_3(x, y, z):
check((x & y) & z == x & (y & z),
"(x & y) & z != x & (y & z) for", x, y, z)
check((x | y) | z == x | (y | z),
"(x | y) | z != x | (y | z) for", x, y, z)
check((x ^ y) ^ z == x ^ (y ^ z),
"(x ^ y) ^ z != x ^ (y ^ z) for", x, y, z)
check(x & (y | z) == (x & y) | (x & z),
"x & (y | z) != (x & y) | (x & z) for", x, y, z)
check(x | (y & z) == (x | y) & (x | z),
"x | (y & z) != (x | y) & (x | z) for", x, y, z)
def test_bitop_identities(maxdigits=MAXDIGITS):
print "long bit-operation identities"
for x in special:
test_bitop_identities_1(x)
digits = range(1, maxdigits+1)
for lenx in digits:
x = getran(lenx)
test_bitop_identities_1(x)
for leny in digits:
y = getran(leny)
test_bitop_identities_2(x, y)
test_bitop_identities_3(x, y, getran((lenx + leny)/2))
# ------------------------------------------------- hex oct repr str atol
def slow_format(x, base):
if (x, base) == (0, 8):
# this is an oddball!
return "0L"
digits = []
sign = 0
if x < 0:
sign, x = 1, -x
while x:
x, r = divmod(x, base)
digits.append(int(r))
digits.reverse()
digits = digits or [0]
return '-'[:sign] + \
{8: '0', 10: '', 16: '0x'}[base] + \
join(map(lambda i: "0123456789ABCDEF"[i], digits), '') + \
"L"
def test_format_1(x):
from string import atol
for base, mapper in (8, oct), (10, repr), (16, hex):
got = mapper(x)
expected = slow_format(x, base)
check(got == expected, mapper.__name__, "returned",
got, "but expected", expected, "for", x)
check(atol(got, 0) == x, 'atol("%s", 0) !=' % got, x)
# str() has to be checked a little differently since there's no
# trailing "L"
got = str(x)
expected = slow_format(x, 10)[:-1]
check(got == expected, mapper.__name__, "returned",
got, "but expected", expected, "for", x)
def test_format(maxdigits=MAXDIGITS):
print "long str/hex/oct/atol"
for x in special:
test_format_1(x)
for i in range(10):
for lenx in range(1, maxdigits+1):
x = getran(lenx)
test_format_1(x)
# ----------------------------------------------------------------- misc
def test_misc(maxdigits=MAXDIGITS):
print "long miscellaneous operations"
import sys
# check the extremes in int<->long conversion
hugepos = sys.maxint
hugeneg = -hugepos - 1
hugepos_aslong = long(hugepos)
hugeneg_aslong = long(hugeneg)
check(hugepos == hugepos_aslong, "long(sys.maxint) != sys.maxint")
check(hugeneg == hugeneg_aslong,
"long(-sys.maxint-1) != -sys.maxint-1")
# long -> int should not fail for hugepos_aslong or hugeneg_aslong
try:
check(int(hugepos_aslong) == hugepos,
"converting sys.maxint to long and back to int fails")
except OverflowError:
raise TestFailed, "int(long(sys.maxint)) overflowed!"
try:
check(int(hugeneg_aslong) == hugeneg,
"converting -sys.maxint-1 to long and back to int fails")
except OverflowError:
raise TestFailed, "int(long(-sys.maxint-1)) overflowed!"
# but long -> int should overflow for hugepos+1 and hugeneg-1
x = hugepos_aslong + 1
try:
int(x)
raise ValueError
except OverflowError:
pass
except:
raise TestFailed, "int(long(sys.maxint) + 1) didn't overflow"
x = hugeneg_aslong - 1
try:
int(x)
raise ValueError
except OverflowError:
pass
except:
raise TestFailed, "int(long(-sys.maxint-1) - 1) didn't overflow"
# ---------------------------------------------------------------- do it
test_division()
test_bitop_identities()
test_format()
test_misc()
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